Module Name: src
Committed By: maxv
Date: Sun Oct 27 20:17:36 UTC 2019
Modified Files:
src/lib/libnvmm: libnvmm.c nvmm.h
src/sys/dev/nvmm: nvmm.c
Log Message:
Change the way root_owner works: consider the calling process as root_owner
not if it has root privileges, but if the /dev/nvmm device was opened with
write permissions. Introduce the undocumented nvmm_root_init() function to
achieve that.
The goal is to simplify the logic and have more granularity, eg if we want
a monitoring agent to access VMs but don't want to give this agent real
root access on the system.
To generate a diff of this commit:
cvs rdiff -u -r1.17 -r1.18 src/lib/libnvmm/libnvmm.c
cvs rdiff -u -r1.15 -r1.16 src/lib/libnvmm/nvmm.h
cvs rdiff -u -r1.23 -r1.24 src/sys/dev/nvmm/nvmm.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/libnvmm/libnvmm.c
diff -u src/lib/libnvmm/libnvmm.c:1.17 src/lib/libnvmm/libnvmm.c:1.18
--- src/lib/libnvmm/libnvmm.c:1.17 Sun Oct 27 07:08:15 2019
+++ src/lib/libnvmm/libnvmm.c Sun Oct 27 20:17:36 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: libnvmm.c,v 1.17 2019/10/27 07:08:15 maxv Exp $ */
+/* $NetBSD: libnvmm.c,v 1.18 2019/10/27 20:17:36 maxv Exp $ */
/*
* Copyright (c) 2018-2019 The NetBSD Foundation, Inc.
@@ -180,6 +180,29 @@ nvmm_init(void)
}
int
+nvmm_root_init(void)
+{
+ if (nvmm_fd != -1)
+ return 0;
+ nvmm_fd = open("/dev/nvmm", O_WRONLY | O_CLOEXEC);
+ if (nvmm_fd == -1)
+ return -1;
+ if (nvmm_capability(&__capability) == -1) {
+ close(nvmm_fd);
+ nvmm_fd = -1;
+ return -1;
+ }
+ if (__capability.version != NVMM_KERN_VERSION) {
+ close(nvmm_fd);
+ nvmm_fd = -1;
+ errno = EPROGMISMATCH;
+ return -1;
+ }
+
+ return 0;
+}
+
+int
nvmm_capability(struct nvmm_capability *cap)
{
struct nvmm_ioc_capability args;
Index: src/lib/libnvmm/nvmm.h
diff -u src/lib/libnvmm/nvmm.h:1.15 src/lib/libnvmm/nvmm.h:1.16
--- src/lib/libnvmm/nvmm.h:1.15 Sun Oct 27 07:08:15 2019
+++ src/lib/libnvmm/nvmm.h Sun Oct 27 20:17:36 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: nvmm.h,v 1.15 2019/10/27 07:08:15 maxv Exp $ */
+/* $NetBSD: nvmm.h,v 1.16 2019/10/27 20:17:36 maxv Exp $ */
/*
* Copyright (c) 2018-2019 The NetBSD Foundation, Inc.
@@ -90,6 +90,7 @@ struct nvmm_mem {
typedef uint64_t nvmm_prot_t;
int nvmm_init(void);
+int nvmm_root_init(void);
int nvmm_capability(struct nvmm_capability *);
Index: src/sys/dev/nvmm/nvmm.c
diff -u src/sys/dev/nvmm/nvmm.c:1.23 src/sys/dev/nvmm/nvmm.c:1.24
--- src/sys/dev/nvmm/nvmm.c:1.23 Wed Oct 23 07:01:11 2019
+++ src/sys/dev/nvmm/nvmm.c Sun Oct 27 20:17:36 2019
@@ -1,4 +1,4 @@
-/* $NetBSD: nvmm.c,v 1.23 2019/10/23 07:01:11 maxv Exp $ */
+/* $NetBSD: nvmm.c,v 1.24 2019/10/27 20:17:36 maxv Exp $ */
/*
* Copyright (c) 2018-2019 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nvmm.c,v 1.23 2019/10/23 07:01:11 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nvmm.c,v 1.24 2019/10/27 20:17:36 maxv Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -889,7 +889,7 @@ out:
/* -------------------------------------------------------------------------- */
static int
-nvmm_ctl_mach_info(struct nvmm_ioc_ctl *args)
+nvmm_ctl_mach_info(struct nvmm_owner *owner, struct nvmm_ioc_ctl *args)
{
struct nvmm_ctl_mach_info ctl;
struct nvmm_machine *mach;
@@ -903,7 +903,7 @@ nvmm_ctl_mach_info(struct nvmm_ioc_ctl *
if (error)
return error;
- error = nvmm_machine_get(&root_owner, ctl.machid, &mach, true);
+ error = nvmm_machine_get(owner, ctl.machid, &mach, true);
if (error)
return error;
@@ -930,16 +930,9 @@ nvmm_ctl_mach_info(struct nvmm_ioc_ctl *
static int
nvmm_ctl(struct nvmm_owner *owner, struct nvmm_ioc_ctl *args)
{
- int error;
-
- error = kauth_authorize_device(curlwp->l_cred, KAUTH_DEVICE_NVMM_CTL,
- NULL, NULL, NULL, NULL);
- if (error)
- return error;
-
switch (args->op) {
case NVMM_CTL_MACH_INFO:
- return nvmm_ctl_mach_info(args);
+ return nvmm_ctl_mach_info(owner, args);
default:
return EINVAL;
}
@@ -1047,8 +1040,12 @@ nvmm_open(dev_t dev, int flags, int type
if (error)
return error;
- owner = kmem_alloc(sizeof(*owner), KM_SLEEP);
- owner->pid = l->l_proc->p_pid;
+ if (OFLAGS(flags) & O_WRONLY) {
+ owner = &root_owner;
+ } else {
+ owner = kmem_alloc(sizeof(*owner), KM_SLEEP);
+ owner->pid = l->l_proc->p_pid;
+ }
return fd_clone(fp, fd, flags, &nvmm_fileops, owner);
}
@@ -1060,7 +1057,9 @@ nvmm_close(file_t *fp)
KASSERT(owner != NULL);
nvmm_kill_machines(owner);
- kmem_free(owner, sizeof(*owner));
+ if (owner != &root_owner) {
+ kmem_free(owner, sizeof(*owner));
+ }
fp->f_data = NULL;
return 0;
